Description N´m Ft. Lbs. In. Lbs.
Distribution Housing Screws 2 ± 17
Discharge Line to Compressor Nut 23 17 ±
Discharge Line to Condenser Nut 23 17 ±
Front Fascia Screws 6 ± 53
Front Fascia Grille Insert Screws 2 ± 17
Heater Core Mounting Plate Screws 2 ± 17
Heater Core Sealing Plate Screws 3 ± 26
Hood Latch Screws 14 ± 123
HVAC Housing Bracket Bolt 3 ± 26
HVAC Housing Mounting Nuts 7 ± 62
HVAC Housing Mounting Bolts 4 ± 35
Liquid Line to Condenser Nut 23 17 ±
Liquid Line to Receiver/drier Bolt 11 ± 97
Lower Air inlet Housing Screws 2 ± 17
Mode Door Actuator Screws 2 ± 17
Quarter Trim Panel Attaching Bracket Screws 2 ± 17
Rear Blower Motor Screws 2 ± 17
Rear Blower Motor Power Module Screws (ATC) 2 ± 17
Rear Blower Motor Resistor Block Screws (MTC) 2 ± 17
Rear Capture Plate Screw 2 ± 17
Rear Evaporator Line Seal Plate to Rear Expansion
Valve Nut23 17 ±
Rear Expansion Valve Bracket Nut 23 17 ±
Rear Expansion Valve Bracket Screws 2 ± 17
Rear Expansion Valve to Rear Evaporator Screws 11 ± 97
Rear Floor Heat Duct Screws 2 ± 17
Rear HVAC Housing Screws 2 ± 17
Rear HVAC Housing Mounting Screws 11 ± 97
Rear HVAC Housing Stud Nuts 9 ± 80
Rear Mode Door Actuator Screws 2 ± 17
Receiver/drier Bracket Nuts 10 ± 89
Recirculation Door Actuator Screws 2 ± 17
Refrigerant Lines to Expansion Valve Nut 23 17 ±
Suction Line to Compressor Nut 23 17 ±
Cabin Heater Air Intake Pipe Screws 7 ± 62
Cabin Heater M6 Bolts 7 ± 62
Cabin Heater M8 Bolts 23 17 ±
Cabin Heater Seat Hex Nut 60 44 ±
Underbody Liquid Line Fitting 23 17 ±
Underbody Refrigerant Line Sealing Plate Bolt/Nut 23 17 ±
Underbody Suction Line Fitting 23 17 ±
Upper Air Inlet Housing Screws 2 ± 17
24 - 12 HEATING & AIR CONDITIONINGRS
HEATING & AIR CONDITIONING (Continued)
CONTROLS - FRONT
TABLE OF CONTENTS
page page
A/C COMPRESSOR CLUTCH/COIL
DESCRIPTION.........................13
OPERATION...........................13
DIAGNOSIS AND TESTING
A/C COMPRESSOR CLUTCH COIL........14
STANDARD PROCEDURE
CLUTCH INSPECTION.................15
A/C CLUTCH BREAK-IN................15
REMOVAL.............................15
INSTALLATION.........................16
A/C COMPRESSOR CLUTCH RELAY
DESCRIPTION.........................18
OPERATION...........................18
REMOVAL.............................19
INSTALLATION.........................19
A/C HEATER CONTROL
DESCRIPTION.........................19
STANDARD PROCEDURE
A/C-HEATER CONTROL CALIBRATION.....19
REMOVAL.............................20
INSTALLATION.........................20
A/C PRESSURE TRANSDUCER
DESCRIPTION.........................20
OPERATION...........................20
DIAGNOSIS AND TESTING
A/C PRESSURE TRANSDUCER..........21
REMOVAL.............................21
INSTALLATION.........................21
BLEND DOOR ACTUATOR
DESCRIPTION.........................22
OPERATION...........................22
REMOVAL.............................22
INSTALLATION.........................22
BLOWER MOTOR RELAY
DESCRIPTION.........................23
OPERATION...........................23
REMOVAL.............................24INSTALLATION.........................24
BLOWER MOTOR RESISTOR BLOCK
DESCRIPTION.........................24
OPERATION...........................24
DIAGNOSIS AND TESTING
FRONT BLOWER MOTOR RESISTOR
BLOCK.............................25
REMOVAL.............................25
INSTALLATION.........................25
EVAPORATOR TEMPERATURE SENSOR
DESCRIPTION.........................26
OPERATION...........................27
REMOVAL
RG MODELS.........................27
RS MODELS.........................27
INSTALLATION
RG MODELS.........................27
RS MODELS.........................28
INFRARED TEMPERATURE SENSOR
DESCRIPTION.........................28
OPERATION...........................28
MODE DOOR ACTUATOR
DESCRIPTION.........................29
OPERATION...........................29
REMOVAL.............................29
INSTALLATION.........................30
POWER MODULE - BLOWER MOTOR
DESCRIPTION.........................30
OPERATION...........................30
REMOVAL.............................30
INSTALLATION.........................31
RECIRCULATION DOOR ACTUATOR
DESCRIPTION.........................31
OPERATION...........................31
REMOVAL.............................32
INSTALLATION.........................32
A/C COMPRESSOR CLUTCH/
COIL
DESCRIPTION
The A/C compressor clutch assembly consists of a
stationary electromagnetic A/C clutch field coil with a
zener diode, a pulley bearing and pulley assembly,
and a clutch plate (Fig. 1). These components provide
the means to engage and disengage the A/C compres-
sor from the engine accessory drive belt.The A/C clutch field coil and the pulley bearing
and pulley assembly are both retained on the nose of
the A/C compressor with snap rings. The clutch plate
is splined to the compressor shaft and secured with a
bolt.
OPERATION
The compressor clutch components provide the
means to engage and disengage the compressor from
the engine serpentine accessory drive belt. When the
clutch coil is energized, it magnetically draws the
RSCONTROLS - FRONT24-13
clutch plate into contact with the clutch pulley and
drives the compressor shaft. When the coil is not
energized, the pulley freewheels on the clutch hub
bearing, which is part of the pulley.
A zener diode is connected in parallel with the
clutch electromagnetic coil. This diode controls the
dissipation of voltage induced into the coil windings
by the collapsing of the electromagnetic fields that
occurs when the compressor clutch is disengaged.
The zener diode dissipates this induced voltage by
regulating a current path to ground. This arrange-
ment serves to protect other circuits and components
from potentially damaging voltage spikes in the vehi-
cle electrical system that might occur if the voltage
induced in the clutch coil windings could not be dis-
sipated.
The compressor clutch engagement is controlled by
several components: the heater-A/C controls in the
passenger compartment, the A/C pressure transducer
on the liquid line, the evaporator temperature sensor
on the expansion valve for automatic temperature
control (ATC) system or on the HVAC housing for
manual temperature control (MTC) system, the Pow-
ertrain Control Module (PCM) in the engine compart-
ment, and the compressor clutch relay in the
Integrated Power Module (IPM). The PCM may delay
compressor clutch engagement for up to thirty sec-
onds (Refer to 8 - ELECTRICAL/ELECTRONIC
CONTROL MODULES/POWERTRAIN CONTROL
MODULE - DESCRIPTION - PCM OPERATION).
DIAGNOSIS AND TESTING
A/C COMPRESSOR CLUTCH COIL
The air conditioning compressor clutch coil electri-
cal circuit is controlled by the powertrain control
module (PCM) through the A/C compressor clutch
relay, which is located in the integrated power mod-
ule (IPM) in the engine compartment. Begin testing
of a suspected compressor clutch coil problem by per-
forming the preliminary checks.
PRELIMINARY CHECKS
(1) If the compressor clutch will not engage, verify
the refrigerant charge level (Refer to 24 - HEATING
& AIR CONDITIONING/PLUMBING - FRONT/RE-
FRIGERANT - DIAGNOSIS AND TESTING -
REFRIGERANT CHARGE LEVEL). If the refriger-
ant charge level is OK, go to Step 2. If the refriger-
ant charge level is not OK, adjust the refrigerant
charge as required.
(2) If the A/C compressor clutch still will not
engage, disconnect the wire harness connector for the
A/C pressure transducer and check for battery cur-
rent at the connector with the engine running and
the A/C-heater control set to the A/C mode. If OK, go
to TESTS. If not OK, refer to Body Diagnostic Proce-
dures to perform further diagnosis.
TESTS
(1) Verify the battery state of charge (Refer to 8 -
ELECTRICAL/BATTERY SYSTEM/BATTERY -
DIAGNOSIS AND TESTING).
(2) Connect an ammeter (0 to 10 ampere scale
selected) in series with the clutch coil feed terminal.
Connect a voltmeter (0 to 20 volt scale selected) to
measure voltage across the battery and the clutch
coil.
(3) With the heater-A/C control in the A/C mode
and the blower at low speed, start the engine and
allow it to run at a normal idle speed.
(4) The compressor clutch should engage immedi-
ately, and the clutch coil voltage should be within
two volts of the battery voltage. If the coil voltage is
not within two volts of battery voltage, test the
clutch coil feed circuit for excessive voltage drop. If
the compressor clutch does not engage, refer to Body
Diagnostic Procedures to perform further diagnosis.
(5) For the acceptable A/C clutch coil current draw
specificationsrefer to 24 - HEATING & AIR CONDI-
TIONING - SPECIFICATIONS. Specifications apply
for a work area temperature of 21É C (70É F). If volt-
age is more than 12.5 volts, add electrical loads by
turning on electrical accessories until voltage reads
below 12.5 volts.
(a) If the compressor clutch coil current reading
is zero, the coil is open and must be replaced.
Fig. 1 A/C Compressor Clutch
1 - BOLT
2 - CLUTCH PLATE
3 - PULLEY AND BEARING
4 - FIELD COIL
5 - SNAP RING (2)
6 - SHIM
24 - 14 CONTROLS - FRONTRS
A/C COMPRESSOR CLUTCH/COIL (Continued)
(b) If the compressor clutch coil current reading
is four amperes or more, the coil is shorted and
must be replaced.
STANDARD PROCEDURE
CLUTCH INSPECTION
NOTE: The compressor clutch can be serviced in
the vehicle. The refrigerant system can remain fully-
charged during compressor clutch, pulley, or coil
replacement.
Examine the friction surfaces of the clutch pulley
and the clutch plate for wear. The pulley and plate
should be replaced if there is excessive wear or scor-
ing.
If the friction surfaces are oily, inspect the shaft
and nose area of the A/C compressor for refrigerant
oil. If refrigerant oil is found, the compressor shaft
seal is leaking and the A/C compressor must be
replaced.
Check the clutch pulley bearing for roughness or
excessive leakage of grease. Replace the pulley and
bearing assembly, if required.
A/C CLUTCH BREAK-IN
After a new A/C compressor clutch has been
installed, cycle the compressor clutch approximately
twenty times (five seconds on, then five seconds off).
During this procedure, set the A/C-heater controls to
the A/C Recirculation Mode, the blower motor in the
highest speed position, and the engine speed at 1500
to 2000 rpm. This procedure (burnishing) will seat
the opposing friction surfaces of the compressor
clutch, which provides optimum compressor clutch
torque capability.
REMOVAL
NOTE: The compressor clutch can be serviced in
the vehicle. The refrigerant system can remain fully-
charged during compressor clutch, pulley, or coil
replacement.
(1) Disconnect and isolate the negative battery
cable.
(2) Remove the accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL).
(3) Raise and support the vehicle.
(4) Disconnect the engine wire harness connector
for the compressor clutch coil from the clutch coil pig-
tail wire connector on the top of the A/C compressor.
(5) On models with the 3.3L and 3.8L engines, dis-
engage the retainer on the engine wire harness com-pressor clutch coil take out from the bracket on the
top of the A/C compressor.
(6) On models with the 2.4L, 2.5L and 2.8L
engines, remove all of the compressor mounting bolts
except the upper left (rear of the A/C compressor),
which should only be loosened. Allow the front (pul-
ley end) of the A/C compressor to tilt downward far
enough to access the clutch for removal, then tighten
the loosened upper left compressor mounting bolt.
(7) On models with the 3.3L and 3.8L engines,
remove the two bolts and two nuts that secure the
A/C compressor to the engine. Disengage the mount-
ing ear at the front of the A/C compressor from the
stud on the engine, allow the front (pulley end) of the
A/C compressor to tilt downward far enough to access
the clutch for removal, then reinstall and tighten the
upper left compressor mounting bolt.
(8) Remove the compressor shaft bolt (Fig. 2). A
band-type oil filter wrench or a strap wrench may be
used to secure the clutch during bolt removal.
(9) Tap the clutch plate lightly with a plastic mal-
let to release it from the splines on the compressor
shaft. Remove the clutch plate and shim(s) from the
compressor shaft (Fig. 3).
NOTE: Use care not to lose any of the shim(s).
Fig. 2 A/C Compressor Shaft Bolt
1 - BOLT
2 - COMPRESSOR CLUTCH PLATE
RSCONTROLS - FRONT24-15
A/C COMPRESSOR CLUTCH/COIL (Continued)
REMOVAL
(1) Disconnect and isolate the negative battery
cable.
(2) Remove the cover from the integrated power
module (IPM) (Fig. 8).
NOTE: Refer to the fuse and relay map on the inner
surface of the cover of the IPM for A/C compressor
clutch relay identification and location.
(3) Remove the A/C compressor clutch relay from
the IPM.
INSTALLATION
NOTE: Refer to the fuse and relay map on the inner
surface of the cover of the integrated power module
(IPM) for A/C compressor clutch relay identification
and location.
(1) Position the A/C compressor clutch relay into
the proper receptacle in the IPM.
(2) Align the A/C compressor clutch relay termi-
nals with the terminal cavities in the IPM receptacle.
(3) Push down firmly on the A/C compressor clutch
relay until the terminals are fully seated in the ter-
minal cavities.
(4) Install the cover onto the IPM.
(5) Reconnect the negative battery cable.
A/C HEATER CONTROL
DESCRIPTION
The A/C-heater control is located at the center of
the instrument panel and uses electrical controls.
These controls provide the vehicle operator with a
number of setting options to help control the climate
and comfort within the vehicle. Refer to the owner's
manual in the vehicle glove box for more information
on the suggested operation and use of these controls.
The A/C-heater control cannot be repaired. If faulty
or damaged, the entire unit must be replaced. The
control knobs are available for service replacement.
STANDARD PROCEDURE
A/C-HEATER CONTROL CALIBRATION
The A/C-heater control module must be recali-
brated each time an actuator motor or the control
module is replaced. If the vehicle is so equipped, the
calibration procedure also includes rear HVAC posi-
tions for each actuator motor.
(1) Turn the ignition switch to the On position.
(2) If equipped with the manual temperature con-
trol (MTC) system, press and hold the Rear Wipe/
Wash and Recirculation buttoms for at least five
seconds. If equipped with the automatic temperature
control (ATC) systen, simultaneously press and hold
the Power and Recirculation buttons on the A/C-
heater control for at least five seconds. The MTC
A/C-heater control Rear Wipe/Wash Light Emitting
Diode (LED) and Recirculation LED, or the ATC A/C-
heater control Delay and Recirculation graphics will
begin to flash when the calibration procedure has
begun.
(3) The calibration procedure should take less than
two minutes to complete for the manual A/C-heater
control, and less than twenty seconds for the ATC
A/C-heater control. When the LEDs or graphics stop
flashing, the calibration procedure is complete.
(4) If the LEDs or graphics continue to flash
beyond the two minute (manual) or twenty second
(ATC) calibration time, it indicates that the A/C-
heater control has detected a failure and a Diagnostic
Trouble Code (DTC) has been set. Refer to Body
Diagnostic Procedures to perform further diagnosis.
The LEDs or graphics will continue to flash even
after the ignition switch is cycled Off and On, until a
successful calibration is completed or until the vehi-
cle has been driven about 13 kilometers (8 miles).
Fig. 8 A/C Compressor Clutch Relay
1 - INTEGRATED POWER MODULE (IPM)
2 - A/C COMPRESSOR CLUTCH RELAY
3 - FRONT CONTROL MODULE
RSCONTROLS - FRONT24-19
A/C COMPRESSOR CLUTCH RELAY (Continued)
REMOVAL
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN ACCIDENTAL AIR-
BAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the center bezel from the instrument
panel (Refer to 23 - BODY/INSTRUMENT PANEL/
INSTRUMENT PANEL CENTER BEZEL -
REMOVAL).
(3) Place the instrument panel center bezel unit
face down on a suitable work surface. Take the
proper precautions to protect the center bezel from
cosmetic damage.
(4) If the vehicle is equipped with the optional
Automatic Temperature Control (ATC) system, dis-
connect the infrared sensor jumper harness connector
from the receptacle on the back of the A/C-heater
control (Fig. 9).
(5) Remove the six screws that secure the A/C-
heater control to the back of the instrument panel
center bezel.
(6) Remove the A/C-heater control from the instru-
ment panel center bezel.
INSTALLATION
(1) Position the A/C-heater control onto the back of
instrument panel center bezel.
(2) Install the six screws that secure the A/C-
heater control to the back of the instrument panel
center bezel. Tighten the screws to 2 N´m (17 in.
lbs.).
(3) If the vehicle is equipped with the optional
ATC system, reconnect the infrared sensor jumper
harness connector to A/C-heater control.
(4) Install the center bezel onto the instrument
panel (Refer to 23 - BODY/INSTRUMENT PANEL/
INSTRUMENT PANEL CENTER BEZEL - INSTAL-
LATION).
(5) Reconnect the battery negative cable.
A/C PRESSURE TRANSDUCER
DESCRIPTION
The A/C pressure transducer is a switch that is
installed on a fitting located on the refrigerant liquid
line between the receiver/drier and the expansion
valve in the right rear corner of the engine compart-
ment. An internally threaded hex fitting on the
transducer connects it to the externally threaded
Schrader-type fitting on the liquid line. A rubber
O-ring seals the connection between the transducer
and the liquid line fitting. Three terminals within a
molded plastic connector receptacle on the top of the
transducer connect it to the vehicle electrical system
through a wire lead and connector of the headlamp
and dash wire harness.
The A/C pressure transducer cannot be adjusted or
repaired and, if faulty or damaged, it must be
replaced.
OPERATION
The A/C pressure transducer monitors the pres-
sures in the high side of the refrigerant system
through its connection to a fitting on the liquid line.
The transducer will change its internal resistance in
response to the pressures it monitors. The power-
train control module (PCM) provides a five volt ref-
erence signal and a sensor ground to the transducer,
then monitors the output voltage of the transducer
on a sensor return circuit to determine refrigerant
pressure. The PCM is programmed to respond to this
and other sensor inputs by controlling the operation
of the A/C compressor clutch and the radiator cooling
fan to help optimize air conditioning system perfor-
Fig. 9 A/C-Heater Control ± ATC shown, MTC typical
1 - INFRARED SENSOR CONNECTOR (ATC ONLY)
2 - INFRARED SENSOR HARNESS (ATC ONLY)
3 - A/C-HEATER CONTROL
4 - SCREW (6)
5- INSTRUMENT PANEL CENTER BEZEL
24 - 20 CONTROLS - FRONTRS
A/C HEATER CONTROL (Continued)
BLEND DOOR ACTUATOR
DESCRIPTION
The blend door actuators are reversible, 12-volt
Direct Current (DC), servo motors. Models with the
single zone heater and air conditioner system have a
single blend air door, which is controlled by a single
blend door actuator. Models with the optional dual
zone front heater and air conditioner system have
dual blend air doors, which are controlled by two
blend door actuators. The single zone blend door
actuator is located on the driver's side end of the
HVAC housing, close to the middle of the distribution
housing. In the dual zone system, the same blend
door actuator used for the single zone system
becomes the passenger blend door actuator, and is
mechanically connected to only the passenger side
blend air door. In the dual zone system, a second sep-
arate blend door actuator is also located on the
driver side end of the HVAC housing, close to the
middle of the distribution housing, and is mechani-
cally connected to only the driver's side blend air
door.
The blend door actuators are interchangeable with
each other, as well as with the actuators for the
mode door and the recirculation air door. Each actua-
tor is contained within an identical black molded
plastic housing with an integral wire connector
receptacle. Two integral mounting tabs allow the
actuator to be secured with two screws to the distri-
bution housing. Each actuator also has an identical
output shaft with splines that connects it to the link-
age that drives the proper blend air door. The blend
door actuators do not require mechanical indexing to
the blend door linkage, as they are electronically cal-
ibrated by the heater-A/C control module.
OPERATION
The blend door actuators are connected to the A/C-
heater control through the vehicle electrical system
by a dedicated two-wire lead and connector of the
HVAC wire harness. The blend door actuator(s) can
move the blend-air door(s) in two directions. When
the A/C-heater control pulls the voltage on one side
of the motor connection high and the other connec-
tion low, the blend-air door will move in one direc-
tion. When the A/C-heater control reverses the
polarity of the voltage to the motor, the blend-air
door moves in the opposite direction.
When the A/C-heater control makes the voltage to
both connections high or both connections low, the
blend-air door stops and will not move. The A/C-
heater control uses a feedback signal positioning sys-
tem to monitor the operation and relative position of
the blend door actuator(s) and the blend-air door(s).
The A/C-heater control learns the blend-air door stoppositions during the calibration procedure and will
store a diagnostic trouble code (DTC) for any prob-
lems it detects in the blend door actuator circuits.
The blend door actuators are diagnosed using a
scan tool (Refer to 24 - HEATING & AIR CONDI-
TIONING - DIAGNOSIS AND TESTING and to 24 -
HVAC Electrical Diagnostics for more information).
The blend door actuators cannot be adjusted or
repaired and, if faulty or damaged, they must be
replaced.
REMOVAL
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN ACCIDENTAL AIR-
BAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
NOTE: The single zone heating and air conditioning
system is equipped with a single blend door actua-
tor. The dual zone system has two blend door
actuators, one for the driver side blend air door and
one for the passenger side blend air door. The
same service procedures can be used for each of
these actuators.
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the silencer from beneath the driver
side end of the instrument panel. (Refer to 23 -
BODY/INSTRUMENT PANEL/INSTRUMENT
PANEL SILENCER - REMOVAL).
(3) Disconnect the wire harness connector from the
blend door actuator(s) (Fig. 11).
(4) Remove the two screws that secure the blend
door actuator to the distribution housing.
(5) Remove the blend door actuator.
INSTALLATION
(1) Position the blend door actuator onto the distri-
bution housing. If necessary, rotate the actuator
slightly to align the splines on the actuator output
shaft with those in the blend air door linkage.
(2) Install the two screws that secure the blend
door actuator to the housing. Tighten the screws to 2
N´m (17 in. lbs.).
24 - 22 CONTROLS - FRONTRS
(3) Connect the HVAC wire harness connector to
the blend door actuator.
(4) Install the silencer under the driver side end of
the instrument panel (Refer to 23 - BODY/INSTRU-
MENT PANEL/INSTRUMENT PANEL SILENCER -
INSTALLATION).
(5) Reconnect the battery negative cable.
(6) Perform the heater-A/C control calibration pro-
cedure (Refer to 24 - HEATING & AIR CONDITION-
ING/CONTROLS - FRONT/A/C-HEATER CONTROL
- STANDARD PROCEDURE - HEATER-A/C CON-
TROL CALIBRATION).
BLOWER MOTOR RELAY
DESCRIPTION
The front blower motor relay is an International
Standards Organization (ISO)-type relay (Fig. 12).
Relays conforming to the ISO specifications have
common physical dimensions, current capacities, ter-
minal patterns, and terminal functions. The front
blower motor relay is located in the integrated power
module (IPM) in the engine compartment. See the
fuse and relay map on the inner surface of the cover
of the IPM for front blower motor relay identification
and location.
The black, molded plastic case is the most visible
component of the front blower motor relay. Five male
spade-type terminals extend from the bottom of the
base to connect the relay to the vehicle electrical sys-
tem, and the ISO designation for each terminal ismolded into the base adjacent to each terminal. The
ISO terminal designations are as follows:
²30 (Common Feed)- This terminal is con-
nected to the movable contact point of the relay.
²85 (Coil Ground)- This terminal is connected
to the ground feed side of the relay control coil.
²86 (Coil Battery)- This terminal is connected
to the battery feed side of the relay control coil.
²87 (Normally Open)- This terminal is con-
nected to the normally open fixed contact point of the
relay.
²87A (Normally Closed)- This terminal is con-
nected to the normally closed fixed contact point of
the relay.
The front blower motor relay cannot be adjusted or
repaired. If the relay is damaged or faulty, it must be
replaced.
OPERATION
The blower motor relay is an electromechanical
switch that uses a low current input from the Front
Control Module (FCM) to control the high current
output to the blower motor resistor (manual heater-
A/C control) or blower power module (ATC control).
The movable common feed contact point is held
against the fixed normally closed contact point by
spring pressure. When the relay coil is energized, an
electromagnetic field is produced by the coil wind-
ings. This electromagnetic field draws the movable
relay contact point away from the fixed normally
closed contact point, and holds it against the fixed
normally open contact point. When the relay coil is
de-energized, spring pressure returns the movable
contact point back against the fixed normally closed
contact point. The resistor or diode is connected in
parallel with the relay coil in the relay, and helps to
dissipate voltage spikes and electromagnetic interfer-
ence that can be generated as the electromagnetic
field of the relay coil collapses.
Fig. 11 Blend Door Actuator - LHD Shown, RHD
Typical
1 - WIRE HARNESS CONNECTOR
2 - MODE DOOR ACTUATOR
3 - SCREW (2)
4 - DRIVER BLEND DOOR ACTUATOR (DUAL-ZONE)
5 - HEATER CORE
6 - BLEND DOOR ACTUATOR (SINGLE ZONE) OR PASSENGER
BLEND DOOR ACTUATOR (DUAL-ZONE)
Fig. 12 Front Blower Motor Relay
RSCONTROLS - FRONT24-23
BLEND DOOR ACTUATOR (Continued)